Mixing diverse integrated circuit (IC) technologies in a single integrated circuit package may provide several positive results. The strength of each separate integrated circuit technology can be advantageously applied to a specified segment of an overall system.
For example, consider the application of this principle to the case of a switch mode power supply integrated circuit (IC). The controller block of a switch mode power supply may benefit from the utilization of a wafer process that provides high accuracy and high gain bipolar junction transistors. Greater precision and speed for the amplifiers and voltage references are possible. Such a wafer process would also possess methods for trimming analog accuracy or selecting functional options for the operation of the system. The controller block of the switch mode power supply does not require high voltage or power transistors. Therefore, the controller block could utilize a high density technology than would be obtainable in a monolithic design.
Now consider the power stages of the switch mode power supply. The power stages would benefit from the utilization of a wafer process that optimizes the functions that are performed by the power stages. The power stages of a switch mode power supply typically require high voltage and current handling. The minimum amount of sensitive signal control circuitry would be placed on the power chip in order to avoid interference from the extremely noisy environment that is created by the power switches.
However, there are several functions that must reside (at least in part) on the power chip. One such function comprises the provision of over-current protection. The power chip must comprise current sensing circuits for providing over-current protection. Another such function is the provision of current mode control. The power chip must comprise sensing circuits for performing current mode control methods.
There is a need in the art for a system and method that is capable of providing efficient communication of over-current protection between multiple chips in an integrated circuit. There is also a need in the art for a system and method that is capable of providing efficient communication of current mode control between multiple chips in an integrated circuit. In particular, there is a need in the art for a system and method that is capable of providing efficient communication of over-current protection and current mode control between multiple chips in a switch mode power supply integrated circuit.
Before undertaking the Detailed Description of the Invention below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like.
The term “controller” means any device, system, or part thereof that controls at least one operation. A controller may be implemented in hardware, software, firmware, or combination thereof. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely.
Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior uses, as well as to future uses, of such defined words and phrases.